The present invention relates to a transmission and reception system, and particularly relates to a transmission and reception system for performing transmission and reception of various types of signals through a transmission line.
A home bus system (hereinafter abbreviated to "HBS"), which is about to be put into practice, is a system in which carrier frequencies modulated with predetermined control signals are transmitted through a transmission line to remote locations where the modulated signals are supplied to controlled appliances, such as lighting fixtures or the like, provided inside a home so as to perform predetermined control of the controlled appliances by demodulating the modulated signals.
An HBS of this type is applicable to a system for transmitting and receiving information signals, such as an audio signal, a video signal, or the like, wherein, for example, an audio signal transmitting means is provided at one location, and a receiving means for receiving the audio signal is provided at another location.
In the case where the transmitted audio signal is a stereo signal and the receiving means has only a monaural capability, the system will not operate properly. The same is true of the reverse situation, and for that matter, it is true in any case where the signal type transmitted differs from the signal type for which the receiver is adapted.
In the case where the transmitting means is a television signal transmitting means which can transmit an HD television signal and the receiving means is a television receiver which can receive only an NTSC signal, it is impossible to receive the transmitted television signal by the receiving means because the television signal supplied to the receiver through a transmission line is an HD television signal.